import java.util.Scanner;
         public class MyDCTester  {

            public static void main (String[] args) {
        String expression, again;

        int result;

             try
            {
                   Scanner in = new Scanner(System.in);

                   do
                       {
                       MyDC evaluator = new MyDC();
                         System.out.println ("Enter a valid postfix expression: ");
                       expression = in.nextLine();

                      result = evaluator.evaluate (expression);
                        System.out.println ("That expression equals " + result);
                         System.out.print ("Evaluate another expression [Y/N]? ");
                       again = in.nextLine();
                      System.out.println();
                      }
                 while (again.equalsIgnoreCase("y"));
              }![](http://images2015.cnblogs.com/blog/1071653/201705/1071653-20170503220452023-968944949.jpg)

            catch (Exception IOException)
         {
                 System.out.println("Input exception reported");
            }
        }
 }
